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  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
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<body>
  <p id="box1">old</p>

  <script>
  
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      var op = document.createElement("p");
      op.innerHTML = i
      document.body.appendChild(op)
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   for (var i = 4; i; i --){
      var newP = oldP.cloneNode(i);
      newP.innerHTML = i
      document.body.appendChild(newP)
    }

 
   </script>
</body>
</html>